package com.example.springbootbookv2.filter;

import com.alibaba.druid.support.http.StatViewServlet;
import com.alibaba.druid.support.http.WebStatFilter;
import org.springframework.boot.web.servlet.FilterRegistrationBean;
import org.springframework.boot.web.servlet.ServletRegistrationBean;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;

/**
 *  @Configuration：Spring中有很多的XML配置文件，文件中会配置很多的bean。
 *  在类上添加@Configuration注解，可以理解为该类变成了一个XML配置文件。
 */
@Configuration
public class DruidConfiguration {
    /**
     * @Bean：等同于XML配置文件中的<bean>配置。
     * Spring Boot会把加上该注解的方法的返回值装载进Spring IoC容器，
     * 方法的名称对应<bean>标签的id属性值。
     * 等同于：
     * <bean id="druidStatFilter"
     * class="org.springframework.boot.web.servlet.ServletRegistrationBean">
     * </bean>
     * @return
     */
    @Bean
    public ServletRegistrationBean druidStatViewServle(){
        //ServletRegistrationBean提供类的进行注册.
        ServletRegistrationBean servletRegistrationBean
                = new ServletRegistrationBean(new StatViewServlet(),"/druid/*");
        //添加初始化参数：initParams
        //白名单：
        servletRegistrationBean.addInitParameter("allow","127.0.0.1");
        //IP黑名单 (存在共同时，deny优先于allow)
        // 如果满足deny的话提示:Sorry, you are not permitted to view this page.
        servletRegistrationBean.addInitParameter("deny","192.168.1.73");
        //登录查看信息的账号和密码.
        servletRegistrationBean.addInitParameter("loginUsername","admin");
        servletRegistrationBean.addInitParameter("loginPassword","123456");
        //是否能够重置数据.
        servletRegistrationBean.addInitParameter("resetEnable","false");
        return servletRegistrationBean;
    }

    @Bean
    public FilterRegistrationBean druidStatFilter(){
        FilterRegistrationBean filterRegistrationBean
                = new FilterRegistrationBean(new WebStatFilter());
        //添加过滤规则.
        filterRegistrationBean.addUrlPatterns("/*");
        //添加需要忽略的格式信息.
        filterRegistrationBean.addInitParameter("exclusions",
                "*.js,*.gif,*.jpg,*.png,*.css,*.ico,/druid/*");
        return filterRegistrationBean;
    }
    /**
     * 类ServletRegistrationBean和FilterRegistrationBean：
     * 在DruidConfiguration.java这个配置文件中我们配置了两个类：
     * druidStatViewServlet和druidStatFilter，
     * 并且通过注册类ServletRegistrationBean和FilterRegistrationBean
     * 实现Servlet和Filter类的注册。
     */
}
